JP5385877B2 - electromagnetic switch - Google Patents

Description

  The present invention relates to an electromagnetic switch including a contact device having a stationary contact and a movable contact inserted in a current path, and an electromagnet for driving the movable contact.

  As this type of electromagnetic switch, for example, a hollow cavity is formed by an upper part of an annular core base, a bottom part of the annular core base, and a core outer wall connecting the outer peripheral edges of the upper part of the core base and the bottom part of the core base. In addition to mounting an exciting coil in the hollow cavity, a cylindrical core center is inserted into the central opening in the upper part of the core base to form a core assembly, and a bottomed cylindrical member is externally fitted to the outer periphery of the core center. A movable plunger facing the lower surface of the core center through a predetermined gap is disposed in the bottomed cylindrical member, and an armature shaft that extends upward through the core center and holds a movable contact is fixed to the plunger. A hermetic relay device has been proposed (see, for example, Patent Document 1).

  In addition, a cylindrical portion fitted into the cylindrical portion of the bobbin individually on the upper side and the lower side of the bobbin having flange portions at both ends of the cylindrical portion around which the excitation coil is wound, and a flange portion formed on the outside thereof A first yoke and a second yoke having a movable iron core are slidably disposed on an inner peripheral surface of the second yoke, and a movable contact is held on the movable iron core via a connecting shaft. An electromagnetic switching device having the above-described configuration has been proposed (see, for example, Patent Document 2).

JP-T 9-510040 JP 2006-19148 A

  By the way, in the conventional example described in the above-mentioned patent document 1, the contact surface of the core center serving as the fixed iron core and the contact surface of the plunger serving as the movable iron core are separated from each other by a predetermined gap on the inner peripheral side of the exciting coil. A bottomed cylindrical member that is externally fitted to the outer peripheral surface of the core center is required to guide the movable iron core. As described above, when the armature surfaces of the fixed iron core and the movable iron core are arranged on the center side of the exciting coil, the area of the armature that becomes a requirement for efficiently outputting the attractive force with a small stroke and the exciting coil There is an unsolved problem that the two requirements of increasing the coil winding amount cannot be satisfied at the same time. That is, when expanding the contact area, it is necessary to increase the inner diameter of the bobbin around which the exciting coil is wound, and this reduces the amount of coil winding. Conversely, if the bobbin's inner diameter is reduced to increase the coil winding amount, it is not possible to secure a contact area between the fixed iron core and the movable iron core, and there is a trade-off between expanding the contact area and increasing the coil winding amount. Off relationship. For this reason, there is an unsolved problem that suction force cannot be output efficiently with a small stroke.

In addition, a bottomed cylindrical member is required to guide the movable iron core, the number of parts increases, the inner diameter of the bottomed cylindrical member needs to be highly accurate, and the bottomed cylindrical member is specially drawn. Therefore, there are unsolved problems such as an increase in manufacturing cost.
In the conventional example described in Patent Document 2, a special bottomed cylindrical member is not required, but the movable iron core is guided by the second yoke. Therefore, the inner diameter of the second yoke is increased. As with the conventional example described in Patent Document 1 described above, there is a trade-off relationship between the increase in the contact area and the increase in the coil winding amount, and the suction force is efficiently used with a small stroke. There is an unresolved problem that it cannot be output automatically.

  Therefore, the present invention has been made paying attention to the unsolved problems of the above-described conventional example, and it is not necessary to form a guide surface for guiding the movable iron core in the exciting coil, and the suction force can be efficiently generated with a small stroke. It aims at providing the electromagnetic switch which can output to.

In order to achieve the above object, an electromagnetic switch according to an embodiment of the present invention is provided for a pair of fixed contacts and a pair of fixed contacts that are fixed within an arc extinguishing chamber container at a predetermined interval. A contact device having a movable contact arranged so as to be able to contact and separate, and an electromagnet device that drives the movable contact, the electromagnet device passing through a cylindrical excitation coil and the center of the excitation coil A fixed iron core, a magnetic yoke that covers the outside of the exciting coil, a movable iron core that is movably disposed in the arc extinguishing chamber container so as to face the fixed iron core and the magnetic yoke , and supports the movable contactor And the contact surfaces of the fixed iron core and the magnetic yoke are formed on the contact device side from the exciting coil.

According to this configuration, since the contact surfaces of the fixed iron core and the magnetic yoke are formed on the contact device side of the exciting coil, there is no need to provide a movable iron core in the exciting coil, and the armature is increased while increasing the coil winding amount. The area can be increased.
An electromagnetic switch according to another embodiment of the present invention is characterized in that three or more contact surfaces are formed on the fixed iron core and the magnetic yoke.

According to this configuration, since the three or more contact surfaces are formed on the fixed core and the magnetic yoke, the contact area can be easily increased.
Further, in the electromagnetic switch according to another aspect of the present invention, the fixed iron core has a bar portion inserted into the excitation coil and the contact point of the excitation coil connected to an end portion of the bar portion on the contact device side. Two or more opposing plates that are formed in a T shape with a flat plate portion covering the device side end portion, and that the magnetic yoke opposes at least two or more ends of the flat plate portion of the fixed iron core via a magnetic gap. It has the part.

According to this configuration, one armature surface constituting the magnetic circuit is formed by the flat plate portion of the fixed iron core on the contact device side of the exciting coil, and the other two or more armature surfaces are formed by the opposing plate portion of the magnetic yoke. It is possible to increase the contact area while increasing the coil winding amount.
An electromagnetic switch according to another aspect of the present invention is characterized in that the opposing plate portion of the magnetic yoke is covered with a nonmagnetic member.

According to this configuration, the opposing plate portion of the magnetic yoke can be opposed to the movable iron core via the nonmagnetic gap, and release characteristics when the contact device is opened can be ensured.
An electromagnetic switch according to another embodiment of the present invention is characterized in that the nonmagnetic member is the arc extinguishing chamber container.

According to this configuration, it is not necessary to prepare a nonmagnetic member separately, and the number of parts can be reduced.
In the electromagnetic switch according to another aspect of the present invention, the movable iron core is urged toward the contact device by a return elastic body, and is guided to be moved up and down by a guide member, and further holds the movable contact. The contactor holder is fixed.
According to this configuration, the movable iron core can be guided up and down by the guide member in the arc extinguishing chamber container.

  According to the present invention, since the contact surface between the movable iron core and the fixed iron core of the electromagnet device is formed on the contact device side from the exciting coil, the movable iron core is not disposed in the central portion of the exciting coil. Since there is no need to provide a guide member for guiding the number of parts, the number of parts can be reduced by this amount, and since only the fixed iron core has to be disposed without providing a contact surface on the center side of the excitation coil, It is possible to increase the winding amount, and further, it is possible to secure a large contact area between the fixed iron core and the movable iron core, and to obtain an effect that the suction force can be efficiently output with a small stroke. .

It is sectional drawing which shows one Embodiment at the time of applying this invention to an electromagnetic contactor. It is the sectional view on the AA line of FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a sectional view showing an example in which the contact device of the present invention is applied to an electromagnetic contactor as an electromagnetic switch. In FIG. 1, reference numeral 1 denotes a contact device, and a DC operation type electromagnet device 2 is disposed on the lower surface side of the contact device 1.
The contact device 1 has an arc-extinguishing chamber container 3 made of, for example, a non-magnetic material and a non-ferrous metal or synthetic resin subjected to insulation treatment, and the contact mechanism 4 is disposed in the arc-extinguishing chamber container 3. The arc-extinguishing chamber container 3 includes a bottomed cylindrical body 3a whose lower end surface is opened and a bottom plate portion 3b that closes the lower end surface of the bottomed cylindrical body 3a. The bottom plate portion 3b has a convex portion 3c projecting downward in the central portion, and an insertion hole 3d through which a shaft portion 12a of the fixed iron core 12 described later is inserted is formed at the center position of the convex portion 3c.

The contact mechanism 4 includes fixed contacts 4 a and 4 b and a movable contact 5. The fixed contacts 4a and 4b are fixedly supported on the opposing wall surface of the bottomed cylindrical body 3a of the arc-extinguishing chamber container 3 by separating the inner end by a predetermined distance and projecting the outer end to the outside of the arc-extinguishing chamber container 3. Has been.
Moreover, the movable contact 5 is formed in a flat plate shape, and is opposed to the upper end side of the fixed contacts 4a and 4b so as to be able to contact and separate at a predetermined distance. The movable contact 5 is attached to the contact holder 6 while being urged downward by a contact spring 7.

  An electromagnet device 2 is disposed on the lower surface side of the arc extinguishing chamber 3. The electromagnet device 2 includes a coil bobbin 10 including a cylindrical portion 10a whose axial direction is the vertical direction and flange portions 10b and 10c that protrude outward from both ends thereof. An exciting coil 11 is wound around a cylindrical space surrounded by the cylindrical portion 10a and the flange portions 10b and 10c of the coil bobbin 10.

  A fixed iron core 12 is inserted through the inner peripheral surface of the cylindrical portion 10 a of the coil bobbin 10. The fixed iron core 12 is formed in a T shape by a shaft portion 12a inserted into the cylindrical portion 10a of the coil bobbin 10 and a flat plate portion 12b extending in a direction perpendicular to the axis from the upper end of the shaft portion 12a on the contact device 1 side. ing. Here, the upper surface of the flat plate portion 12 b is set to be lower than the upper surface of the bottom plate portion 3 b of the arc extinguishing chamber container 3.

  A magnetic yoke 13 is disposed outside the coil bobbin 10. The magnetic yoke 13 includes a bottom plate portion 13a that supports the flange portion 10c, a cylindrical portion 13b that extends upward from the outer peripheral edge of the bottom plate portion 13a, and a flat plate portion of the fixed iron core 12 that extends inward from the upper end of the cylindrical portion 13b. It is comprised with a pair of flange part 13c as an opposing board part which opposes the outer end of 12b through a predetermined gap.

  And the flat plate part 12b of the fixed iron core 12 is fixed inside the convex part 3c formed in the bottom plate part 3b of the arc-extinguishing chamber container 3 described above, and the upper surface of the flange part 13c of the magnetic yoke 13 is the arc-extinguishing chamber container. 3 is in contact with the lower surface of the outer side of the convex portion 3c in the bottom plate portion 3b. That is, the upper surface of the flange portion 13 c of the magnetic yoke 13 is covered with the bottom plate portion 3 b of the arc extinguishing chamber container 3 to form a nonmagnetic gap.

  In the arc extinguishing chamber container 3, the movable iron core 14 is movably arranged in the vertical direction so as to face the flat plate portion 12 b of the fixed iron core 12 of the electromagnet device 2 and the flange portion 13 c of the magnetic yoke 13 from above. Yes. As shown in FIG. 2, the movable iron core 14 is formed in a flat plate shape, and guide recesses 14a and 14b having a semicircular cross section, for example, are formed at both front and rear ends thereof. These guide recesses 14a and 14b are guide members formed with semicircular guide projections 15a and 15b that engage with a pair of front and rear guide recesses 14a and 14b that are formed to project upward from the bottom plate portion of the arc-extinguishing chamber container 3. It is guided in the vertical direction by 15c and 15d.

  A return spring 16 as a return elastic member is disposed between the upper surface of the fixed iron core 12 and the lower surface of the movable iron core 14, and the movable iron core 14 is separated upward from the flat plate portion 12 b of the fixed iron core 12 by the return spring 16. It is energized in the direction to do. As shown in FIG. 1, the upper position of the movable iron core 14 is regulated by locking pieces 15e and 15f formed on the upper portions of the guide members 15c and 15d.

A contact holder 6 is fixed to the center of the upper surface of the movable core 14 and extends upward through the fixed contacts 4a and 4b.
In this embodiment, on the outer side of the exciting coil 11 of the electromagnet device 2 on the contact device 1 side, a flat plate portion 12b of the fixed iron core 12, and both left and right end portions of the flat plate portion 12b are horizontally spaced with a predetermined gap. A pair of flange portions 13c of the opposing magnetic yoke 13 is disposed. Therefore, the flat plate portion 12b of the fixed iron core 12 forms one armature surface Fa constituting the magnetic circuit, and the two armature surfaces Fb and Fc in which the pair of flange portions 13c of the magnetic yoke 13 serve as the other armature surface. Form.

Next, the operation of the above embodiment will be described.
Now, when the exciting coil of the electromagnet device 2 is in a non-energized state in which no direct current is supplied, no magnetic flux flows through the magnetic circuit formed by the fixed iron core 12 and the magnetic yoke 13, and a pair of the fixed iron core 12 and the magnetic yoke 13 is used. The three armature surfaces Fa, Fb, and Fc formed with the flange portion 13c are in a state where no attractive force acts.

  For this reason, the movable iron core 14 is biased upward by the return spring 16 so as to be separated from the flat plate portion 12b of the fixed iron core 12, and the upper surface of the movable iron core 14 is formed on the upper surfaces of the guide members 15c and 15d. The upper position is regulated by contacting the pieces 15e and 15f.

  In this state, a gap of about 2 mm, for example, is formed between the upper surface of the flat plate portion 12 b of the fixed iron core 12 and the lower surface of the movable iron core 14. At this time, the movable contact 5 held by the contact holder 6 formed on the movable iron core 14 is urged downward by the contact spring 7, but between the movable contact 5 and the fixed contacts 4a and 4b. Is about 2 mm apart, the contact device 1 is in an open state, and the electric power supplied to the one fixed contact 4a is not supplied to the fixed contact 4b side, and is in a power cut-off state.

  When the exciting coil 11 is energized from the opened state of the contact device 1, a magnetic flux flows through a magnetic circuit formed by the fixed iron core 12 and the magnetic yoke 13 surrounding the exciting coil 11, and the fixed iron core 12 and the magnetic yoke A suction force is generated by the three armature surfaces Fa, Fb, and Fc formed by the 13 pairs of flange portions 13 c, and the movable iron core 14 is attracted downward against the return spring 16.

  Therefore, the movable iron core 14 moves downward to come into contact with the upper surface of the bottom plate portion 3 b of the arc extinguishing chamber container 3, and the lower surface of the movable iron core 14 is a pair of flange portions 13 c of the magnetic yoke 13 and the bottom plate of the arc extinguishing chamber container 3. It will oppose through the nonmagnetic gap formed in the part 3b. At this time, the movable contact 5 held by the contact holder 6 formed on the movable iron core 14 also moves downward, and contacts with the contact pressure by the contact spring 7 between the fixed contacts 4a and 4b. Thereby, between the fixed contacts 4a and 4b is brought into conduction by the movable contact 5, and the contact device 1 is closed.

  When the energization to the exciting coil 11 is stopped from the closed state of the contact device 1, the attractive force on the contact surfaces Fa, Fb and Fc between the fixed iron core 12 of the electromagnet device 2 and the pair of flange portions 13c of the magnetic yoke 13 is increased. Disappear. As a result, the movable iron core 14 moves upward away from the contact surfaces Fa, Fb and Fc formed by the fixed iron core 12 and the flange portion 13c of the magnetic yoke 13 by the return spring 16. For this reason, the movable contact 5 moves upward, moves away from the fixed contacts 4a and 4b, and the contact device 1 returns to the open state.

  Thus, according to the embodiment, the coil bobbin 10 in which the contact surfaces Fa, Fb, and Fc formed by the fixed iron core 12 of the electromagnet device 2 and the pair of flange portions 13c of the magnetic yoke 13 are wound with the exciting coil 11 is provided. Is formed on the contact device 1 side. For this reason, only the shaft portion 12a of the fixed iron core 12 is inserted into the exciting coil 11, and there is no movable portion. Therefore, there is no need to arrange a guide member in the exciting coil 11, and the number of parts accordingly. Can be reduced.

Moreover, since the shaft portion 12a of the fixed core 12 inserted into the exciting coil 11 only needs to form a magnetic path, a large cross-sectional area is not required, and the inner diameter of the cylindrical portion 10a of the coil bobbin 10 is reduced. Thus, it is possible to secure a sufficient amount of winding of the exciting coil 11 wound around the coil bobbin 10 and secure a magnetic flux.
In addition, three contact surfaces Fa, Fb, and Fc formed by the fixed iron core 12 and the pair of flange portions 13c of the magnetic yoke 13 are formed on the contact device 1 side of the coil bobbin 10, and coil winding is performed. Since there is no trade-off with the amount and a large contact area can be secured, the electromagnet device 2 can efficiently output the attractive force with a small stroke.

  Moreover, since the bottom plate part 3b of the arc-extinguishing chamber container 3 can be used for the nonmagnetic gap necessary for ensuring the release characteristics of the movable contactor 5 from the closed state to the open state of the contact device 1, it is possible to use separately. It is not necessary to form a nonmagnetic gap, and the number of parts can be reduced by this amount. At this time, in order to ensure the strength of the arc-extinguishing chamber container 3, even when the thickness of the arc-extinguishing chamber container 3 is increased, the flat plate portion 12b of the fixed iron core 12 is formed in the arc-extinguishing chamber container 3 as described above. As a result, it is possible to reduce the magnetic resistance and ensure the necessary magnetic characteristics.

In addition, in the said embodiment, although the case where the flat plate part 12b of the stationary iron core 12 in the electromagnet apparatus 2 was arrange | positioned in the arc-extinguishing chamber container 3 was demonstrated, it is not limited to this, The arc-extinguishing chamber container 3 When the thickness can be reduced to reduce the magnetic resistance, the flat plate portion 12b of the fixed iron core 12 may be disposed outside the arc-extinguishing chamber container 3.
In the above embodiment, the case where the two armature surfaces Fb and Fc are formed on the magnetic yoke 13 has been described. However, the present invention is not limited to this, and the flange portion 13c of the magnetic yoke 13 is fixed to the fixed iron core 12. It may be provided on the other facing surface of the flat plate portion 12b to form three or more contact surfaces.

  Furthermore, in the said embodiment, although the case where this invention was applied to an electromagnetic contactor was demonstrated, it is not limited to this, This invention can be applied to other electromagnetic switches, such as an electromagnetic relay. .

  DESCRIPTION OF SYMBOLS 1 ... Contact apparatus, 2 ... Electromagnet apparatus, 3 ... Arc-extinguishing chamber container, 3a ... Bottomed cylinder, 3b ... Bottom plate part, 3c ... Convex part, 4a, 4b ... Fixed contact, 5 ... Movable contact, 6 ... Contact holder, 7 ... contact spring, 10 ... coil bobbin, 11 ... excitation coil, 12 ... fixed iron core, 12a ... shaft portion, 12b ... flat plate portion, 13 ... magnetic yoke, 13a ... bottom plate portion, 13b ... cylindrical portion, 13c ... Flange portion, 14 ... movable iron core, 15c, 15d ... guide member, 15e, 15f ... locking piece, 16 ... return spring

Claims (6)

A contact device having a pair of fixed contacts fixed in the arc extinguishing chamber container at a predetermined interval, and a movable contact disposed so as to be able to contact with and separate from the pair of fixed contacts;
An electromagnet device for driving the movable contact;
The electromagnet device includes a cylindrical excitation coil, a fixed iron core that passes through the center of the excitation coil, a magnetic yoke that covers the outside of the excitation coil, and the arc-extinguishing chamber container facing the fixed iron core and the magnetic yoke. And a movable iron core that is movably disposed within and supports the movable contact, and a contact surface of the fixed iron core and the magnetic yoke is formed on the contact device side from the exciting coil. An electromagnetic switch.   The electromagnetic switch according to claim 1, wherein at least three armature surfaces are formed on the fixed iron core and the magnetic yoke.   The fixed iron core is formed in a T-shape with a bar portion inserted into the excitation coil and a flat plate portion covering the contact device side end of the excitation coil connected to the contact device side end of the rod portion. 3. The magnetic yoke according to claim 1, wherein the magnetic yoke has two or more opposing plate portions that are opposed to at least two or more ends of the flat plate portion of the fixed iron core via a magnetic gap. Electromagnetic switch.   The electromagnetic switch according to claim 3, wherein the opposing plate portion of the magnetic yoke is covered with a nonmagnetic member.   The electromagnetic switch according to claim 4, wherein the nonmagnetic member is the arc extinguishing chamber container.   The movable iron core is urged toward the contact device by a return elastic body, is guided by a guide member to be movable up and down, and further has a contact holder for holding the movable contact. Item 6. The electromagnetic switch according to any one of Items 1 to 5.

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